Is it normal i cant communicate with room mate?

How do I communicate with my room mate. They get angry if I ask when they are getting home, whats for dinner or like if I should make dinner. They say that it does not effect the house but we all have to eat, and if they want something else I kind of need to know that. They however refuse to speak about that since they say its an invasion of privacy and so if I want to know they get to go through my texts and emails since its exactly the same. How do I get them to communicate. Its very frustrating. They dont know how to plan shit and they just kind of bitch when you need to work around them.

A lot of times they dont come home and tell us to make dinner, or if they are picking something up no purpose in making dinner. However if we at the house already make dinner and they planned on making something else they will get upset. Yet they refuse to communicate this with us and want in return for us to give them all our personal information. I just dont know how to communicate how it effects us. They just dont get it. How do I deal with unreasonable Room mate?